1. Field of the Invention
The present invention relates generally to a synchronous slide-aid device for electronic apparatus, and more particularly to a relative-rotation synchronous movement-aid device including a linking arm and a rotational wheel assembled with the linking arm. The relative-rotation synchronous movement-aid device is mounted on a slidable or movable apparatus body. In operation, the relative-rotation synchronous movement-aid device serves to increase the synchronous movement effect and operational stability of the slide device. Accordingly, the problems of elastic fatigue and difficulty in controlling the assembling quality with the conventional transmission belt are overcome.
2. Description of the Related Art
It is known that various freely reciprocally movable or slidable slide cover systems have been developed and applied to different electronic devices such as mobile phones, laptops, PDA, digital imagers and electronic books. The slide cover can be moved and opened/closed.
The above slide cover module or slide cover assembly generally includes a movable frame, a linking board, multiple elastic members, linking wires and guide rails with specific configurations. These components cooperate with each other to help in opening/closing the slide cover. In the case that such slide cover module is applied to a relatively heavyweight electronic product necessitating longer movement distance, when operated, (for example, when a lateral push force is applied to one single side of the slide cover assembly), the slide cover assembly or mechanism tends to shake or deflect to affect the stability of movement of the slide cover assembly.
In order to solve the problem of shake or deflection of the slide cover assembly or mechanism, a slide cover assembly with wires or transmission belt for helping in sliding the slide cover has been developed. In such device, a first transmission unit and a second transmission unit are respectively arranged on two sides of the electronic apparatus. The first and second transmission units are composed of idlers. A transmission belt is wound around the first and second transmission units. When pushing the slide cover module to move, the transmission belt and the first and second transmission units cooperate with each other to keep the slide mechanism synchronously moving so as to avoid deflection or shake of the slide cover module.
In the above slide cover mechanism, the wires or transmission belt is elastic. Therefore, in the cooperative driving process, the transmission of kinetic energy will be delayed. As a result, the slide cover module will still deflect or shake. Especially, after a period of use, the original preset force of the assembled wires or transmission belt will decline due to elastic fatigue. This will lead to deterioration of the synchronous movement effect of the transmission mechanism.
In practice, in case of more serious elastic fatigue of the wires or transmission belt, the wires or transmission belt may detach from the idlers or rollers during sliding operation of the slide cover module. Under such circumstance, the slide device will lose its synchronous movement effect.
Moreover, as well known by those skilled in this field, when assembled, the wires or transmission belt needs to be in a tensioned state. This causes more difficult in controlling the quality in wiring and assembling process. As a result, the ratio of good products can be hardly increased and the assembling time can be hardly shortened. Accordingly, the manufacturing cost for the product is increased.
It is therefore tried by the applicant to provide a relative-rotation synchronous movement-aid device to overcome the above shortcomings existing in the conventional slide cover module. The synchronous movement-aid device includes specifically designed transmission mechanism and cooperative structures to eliminate the problem of delay of transmission of kinetic energy with the wires or transmission belt. In practice, not only the problem of shake or deflection of the slide cover is solved, but also the synchronous movement effect and operational stability of the slide device are increased.